This invention relates to a cloth spreading machine, and more particularly to a manually operated drive control apparatus for a cloth spreading machine.
Drive speed control apparatus for cloth spreading machines are known in the art, such as those disclosed in the U.S. Merrill Pat. No. 3,540,720, issued Nov. 17, 1970, the Paterson U.S. Pat. No. 3,713,642, issued on Jan. 30, 1973, and the Smith U.S. Pat. No. 4,082,258, issued Apr. 4, 1978.
All of the above patents disclose cloth spreading machines driven by electrical motors controlled by rheostats or powerstats, which are actuated by manual control mechanisms of different types. These manual control mechanisms are designed to permit an operator walking alongside the moving cloth spreading machine to control the speed of the machine by manipulating a handle, which is linked to means for varying the electrical resistance in a rheostat or potentiometer.
Both the Merrill and Paterson patents include an elongated rigid link bar as a means for connecting the handle member to the wiper of the electrical rheostat.
The Smith patent discloses an elongated control shaft, having radial handles at opposite ends thereof, which is rotatably mounted along the side of the machine, and is provided with link means to a rotary pontentiometer or "Powerstat," so that the rotation of the control shaft by the handle at either end will vary the speed of the motor and therefore the speed of the cloth spreading machine.
Only the Paterson patent discloses a manually operable switch 81 for reversing the direction of the electric motor, and thereby the direction of movement of the cloth spreading machine. However, this reversing switch forms no part of the operating handle mechanism which controls the speed of the motor.
Both the handle members disclosed in the Merrill and Paterson patents are difficult to manipulate, because they require an exceptional amount of strength in the hand or wrist of the operator, and incorporates a minimal mechanical advantage between the handle member and the wiper of the rheostat.
None of the Merrill, Paterson, or Smith patents disclose the combination of a speed control actuator and directional control actuators, much less a brake control actuator, assembled on an elongated handle member capable of being longitudinally shifted and rotated about its own longitudinal axis.